Add DeferredSecurityContext

Issue gh-12023

core/src/main/java/org/springframework/security/core/context/DeferredSecurityContext.java

@@ -0,0 +1,38 @@
+/*
+ * Copyright 2002-2022 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.security.core.context;
+
+import java.util.function.Supplier;
+
+/**
+ * An interface that allows delayed access to a {@link SecurityContext} that may be
+ * generated.
+ *
+ * @author Steve Riesenberg
+ * @since 5.8
+ */
+public interface DeferredSecurityContext extends Supplier<SecurityContext> {
+
+	/**
+	 * Returns true if {@link #get()} refers to a generated {@link SecurityContext} or
+	 * false if it already existed.
+	 * @return true if {@link #get()} refers to a generated {@link SecurityContext} or
+	 * false if it already existed
+	 */
+	boolean isGenerated();
+
+}